,,introduction ,,of ,,the ,,locomotive ,,safety ,,truck by ,john ,h4 ,white ,paper #bd pages #aag-aca1 from ,,contributions ,,from ,,the ,,museum ,,of ,,history ,,and ,,technology ,,united ,,states ,,national ,,museum ,bulletin #bbh ,smithsonian ,institution ,washington1 ,d4,c41 #aifa ,contributions from ,the ,museum of ,history and ,technology3 ,paper #bd ,introduction of ,the ,locomotive ,safety ,truck ,john ,h4 ,white ,,introduction ,,of ,,the ,,locomotive ,,safety ,,truck ,john ,h4 ,white ,pioneer railroading was dangerous4 ,with increased speed and density of traffic came an increase in catastrophic wrecks that forced operators to take heed for the safety of their passengers and freight4 ,this safety was painfully achieved through the slow process of improving equipment part by part4 ,antedating such spectacular post-,civil ,war advances as the steel rail1 automatic coupler1 and airbrake1 was the invention of the safety truck for locomotives4 ,intended to lead the bobbing1 weaving locomotive around curves on the rough track of the early roads1 it did much to reduce the all too numerous derailments that were a major cause of accidents4 ,the ,author3 ,john ,h4 ,white1 is associate curator1 in charge of land transportation1 in the ,smithsonian ,institution's ,museum of ,history and ,technology1 ,united ,states ,national ,museum4 ,american railroads of the early #aith century were cheaply and hastily built4 ,they were characterized by inferior roadbeds1 steep grades1 sharp curves1 and rough track4 ,in spring1 poor drainage and lack of ballast might cause the track to sink into the soggy roadbed and produced an unstable path4 ,in winter this same roadbed could freeze into a hard and unyielding pavement on which the rolling stock was pounded to pieces4 ,in those pioneering times the demand for new roads left little capital to improve or expand existing lines2 therefore equipment was needed that could accommodate itself to the existing operating conditions4 ,the first locomotives used in this country had been imported from ,england4 ,designed for well-ballasted track with large-radius curves and gentle gradients1 they all too frequently left the rails1 and the unsuitability of the essentially rigid ,british design soon became apparent4 ,the challenge posed by the ,american roadbed was met by ,american mechanics4 ,by the mid-#ahcj's a distinctive ,american locomotive had evolved that might best be described by the word flexible4 ,the basic features of its running gear were a bar frame and equalizing levers to provide vertical relief and a leading truck to provide lateral relief4 ,of these devices the truck was probably the most important1 and more readily than any one component distinguished the ,american running gear from that used by the ,british before #ahfj4 ,illustration3 ,,figure #a4--;,design drawing showing the #d-wheel leading truck1 developed in #ahca by ,john ,b4 ,jervis1 applied to the ,brother ,jonathan4 ,this locomotive1 one of the earliest to use a leading truck1 was built in ,june #ahcb by the ,west ,point ,foundry ,association for the ,mohawk and ,hudson ,rail ,road4 ,the truck is attached to the locomotive frame by a center pin1 but the forward weight of the locomotive is carried by a roller which bears on the frame of the truck4 7,smithsonian photo #cfgaf-;a7 ,it was ,john ,b4 ,jervis who is generally credited with first applying the truck to the locomotive4 ,his design1 shown in figure #a1 was developed in #ahca-cb4 ,its merits quickly became apparent1 and by #ahce it had been universally recognized in this country4 ,the truck successfully led the locomotive around sharp curves1 the resultant #c-point suspension enabled the machine to traverse even the roughest of tracks1 and1 altogether1 the design did far less damage to the lightly built ,u4,s4 lines than did the rigid1 imported engines4#a ,the truck frame1 fabricated from iron straps and castings1 was attached to the locomotive by a pin around which it might rotate4 ,at first the weight was received by rollers or chafing pads mounted on the side beams of the truck4 ,however1 the friction of these bearing surfaces and their location at a considerable distance from the center pin combined to restrict the free movement of the truck4 ,by the early #ahej's the point of bearing was transferred to the center plate1 producing a truck that turned more freely4#b ,illustration3 ,,figure #b4--,the #d-wheel ,bissell truck as shown in the drawing for ,british patent #abgc1 issued ,may #e1 #aheg4 ,illustration3 ,a--,truck frame ,b--,equalizing lever ,c--,locomotive frame ,d--,double incline plane 7,centering device7 ,e--,truck bolster ,f--,swivel pin 7,pivot point7 ,drawn by ,j4 ,h4 ,white4 ,june1 #aifj ,,figure #c4--,typical #d-wheel ,bissell ,safety truck of #ahfj4 ,this drawing is based on plate #fi of ,alexander ,l4 ,holley's1 ,american and ,european ,railway ,practice in the ,economical ,generation of ,steam1 ,new ,york1 #ahfa4 7,smithsonian photo #dfidf7 ,for single axle engines this simple form of truck was entirely satisfactory1 but it proved less satisfactory for #d- and #f-;coupled machines4 ,also1 as train speeds increased1 so did the number of derailments4 ,many of these could be traced to the inability of the engine to negotiate curves at speed4 ,levi ,bissell1 a ,new ,york inventor who investigated this problem in the #ahej's1 correctly analyzed the difficulty4 ,he observed that when the engine was proceeding on straight tracks the leading truck tended to oscillate and chatter about the center pin1 and he noted that it was this action that imparted a fearful pitching motion to the locomotive at speed4 ,the derailments were traced to the action of the truck as the engine entered a curve4 ,this action can be more easily understood from reference to ,bissell's patent drawing in figure #b4 ,for example1 let us say that an #h-wheel engine1 fitted with a center-swing truck1 enters a right-hand curve4 ,the left truck wheels bear hard against the left rail4 ,the drivers jam obliquely across the track1 with the right front and left rear wheels grinding into the rails4 ,as a result1 the locomotive tends to leave the track in the direction of the arrow shown on the figure 7bottom drawing74 ,it will be noted that the truck center pintle is in fact the fulcrum for this leverage4 ,under such strain the truck wheels are particularly likely to leave the rails when they encounter an obstruction4 ,once derailed1 the truck would then spin around on the deadly center pin1 throwing the locomotive over4 ,in effect1 then1 the center pin of the conventional truck extended the rigid wheelbase of the engine1 and caused the truck to act much as would a single set of leading wheels fitted rigidly to the engine frame far ahead of the front driving wheels4 ,bissell proposed to correct the faults of the conventional truck by fitting the locomotives with his invention1 the first practical safety truck to be patented4 ,since the primary requirements were to keep the leading wheel axles at right angles to the rails whether on a straight or curved track1 and to allow the driving axles to remain parallel1 or nearly so1 to the radial line of the curve1 he moved the center pin to a point behind the truck and just in front of the forward driving axle4 ,this shortened the wheelbase of the engine and removed the danger of the pintle serving as a fulcrum between the truck and the driving wheels1 thus allowing them to assume a comfortable position on a curve4 ,illustration3 ,,figure #d4--;,a #d-wheel safety truck fitted with ,a4 ,f4 ,smith's swing-bolster centering device4 ,built by the ,hinkley ,locomotive ,works4 ,from ,gustavus ,weissenborn1 ,american ,locomotive ,engineering and ,railway ,mechanism1 ,new ,york1 #ahga1 pl4 #hh4 ,since the truck could assume the correct angle when entering curves1 it was claimed in the patent specification that1 unless all four wheels were simultaneously lifted off the track1 the truck could pass over quite a considerable obstruction4#c ,bissell further claimed3 ,in running on either a straight or curved track one of the truck wheels often breaks off1 and the truck swivels around on its center pin in consequence1 and throws the engine off the track1 but with my device one wheel1 or even the two wheels on the opposite sides diagonally of the truck might break off and still the truck would not run off1 because its position is set and it has no axis of motion around which it could swing4444 ,the other problem ,bissell wished to correct was the oscillation and chatter of the leading truck4 ,this was accomplished by a simple centering device in the form of a pair of ,v-shaped double incline planes 7,d on fig4 #c7 situated at the center of the truck frame 7,a74 ,the lower planes of the pair were fastened to the truck frame and the upper1 cast in the form of a bridge1 were attached to the locomotive frame 7,c7 by a center plate4 ,but while the portion of the locomotive's weight assigned to the leading wheels was borne at the center of the truck1 as in the conventional design1 the center plate was no longer the point of rotation4 ,on a straight track the ,v's would be at their bottom position and thus prevent the truck from vibrating4#d ,when the locomotive entered a curve the planes allowed its forward weight to bear continuously on all four wheels1 and at the same time controlled any exaggerated swing caused by centrifugal force4 ,the centering device is thus explained in the patent specification 7figure numbers are omitted73 ,i therefore obviate this difficulty the oscillation of the truck by providing two inclined planes 444 formed double as shown and of an angle proportioned to the weight of the forward part of the locomotive and the velocity of the same4444 ,the position of the inclines is such that the blocks ,v's rest in the lowest part of the double inclines when the engine is on a straight track1 and on coming onto a curve the inertia of the engine 444 is expended in going up the inclines1 as the truck moves laterally toward the inner part of the curve2 and on coming onto a straight line the blocks1 descend to the bottom of the inclines and the engine is prevented from acquiring a sidewise or oscillating motion4 ,illustration3 ,,figure #e4--;,detail drawing of the radius-bar truck1 patented by ,william ,s4 ,hudson in #ahfd1 as applied to the ,new ,jersey ,railroad and ,transportation ,company ,no4 #dd4 ,from ,gustavus ,weissenborn1 ,american ,locomotive ,engineering and ,railway ,mechanism1 ,new ,york1 #ahga1 pl4 #h4 ,bissell applied for a ,u4,s4 patent on ,april #bc1 #aheg4 ,his petition was initially denied4 ,a weary debate of several months duration followed between the patent examiner and ,bissell's attorneys4 ,during this time ,bissell was busy promoting the application of his truck even though he had no patent for protection4 ,in ,may of #aheg he showed a working model of his improvement to ,gilbert ,m4 ,milligan1 secretary of the ,central ,railroad ,company of ,new ,jersey4#e ,samuel ,l4 ,moore1 master mechanic of that railroad1 also inspected the model4 ,both were so impressed that it was decided to fit the device to the locomotive ,lebanon1 which at the time was undergoing repairs at the road's ,elizabeth ,port1 ,new ,jersey1 shops4#f ,although the engine was less than #ah months old1 her tires were badly worn and she oscillated at high speed4 ,early in ,june of that year a series of tests were held with the ,lebanon4 ,moore said of these trials3#g ,after the said invention of ,bissell had been applied the engine was run out onto a curve which she turned apparently with nearly as much facility as she would travel on a straight line1 and the forward part of the engine rose on the inclines as the truck entered the curve and remained fixed while running around said curve and then resumed its former position on entering a straight track1 and the trial was pronounced by all who saw it as most satisfactory1 even by those who before pronounced that it would be a failure4 ,at a subsequent trial under a full pressure of steam and a velocity of about thirty miles per hour the entering and leaving the curve was equally satisfactory1 the same being accurately observed by a man located on the cow catcher4 444 ,the engine was run at its greatest possible velocity at least forty miles per hour on a straight track and the previous shaking of the head oscillation was found to be entirely overcome1 and the engine run as steadily as a car would have done4444 ,at one of the trials a bar of iron #c_/d x #d inches was spiked down across one of the rails diagonally of the track1 444 and the employees of the company took the precaution to fill in around the track to facilitate getting the engine back again1 supposing she must jump off2 however on passing over slowly she still kept the track and the speed was increased until she passed over said bar 444 while under a considerable speed4 ,messrs4 ,moore and ,milligan heartily endorsed the truck as a complete success4 ,milligan predicted that#h the time is not far distant when locomotives will be considered incomplete and comparatively unsafe without this improvement particularly on roads which have many curves4 ,illustration3 ,,figure #f4--,the ,new ,jersey ,railroad and ,transportation ,company ,no4 #ab1 built in #ahfh1 was equipped with the radius bar truck1 a modification by ,william ,s4 ,hudson of the original ,bissell truck4 ,the ,general ,darcy and several other engines built at the ,jersey ,city shops of the road1 under the direction of ,john ,headden1 were fitted with the ,hudson truck4 ,note that the radius bar is connected to the truck frame just behind the rear leading wheels4 7,smithsonian photo #dfhjf-l7 ,u4,s4 ,patent ,commissioner ,charles ,mason was so impressed by the evidence of the ,new ,jersey trials1 reinforced by the arguments of ,bissell's attorneys1 that he agreed to grant a ,united ,states patent4#i ,it was issued as no4 #agiac on ,august #d1 #aheg1 and reissued ,october #ah1 #ahfd as no4 #agid4 ,british patent #abgc had been issued earlier 7,may #e1 #aheg71 and patents were also secured in ,france1 ,belgium1 ,austria1 and ,russia4 ,the ,rogers ,locomotive ,works in #aheh was one of the earliest builders to apply the improved truck4 ,by #ahfj they had fitted many of their engines with it and were endorsing the device to prospective customers4 ,in the same year the ,american ,railway ,review noted that the truck was in extensive use1 stating3#aj 444 the advantages of the arrangement are so obvious and its results so well established by practice in this country and ,europe that a treatise on its principles will hardly be needed4 ,it is no longer an experiment2 and the earlier it is applied to all engines1 the better the running and repair accounts will look4 ,the success of ,bissell's invention prompted others to perfect safety trucks for locomotives4 ,alba ,f4 ,smith came forward in #ahfb with the simple substitution of swing links 7fig4 #d7 for the incline planes4#aa ,a swing-bolster truck had been developed #bj years earlier for use on railroad cars1#ab and while ,smith recognized this in his patent1 he based his claim on the specific application of the idea to locomotive trucks4 ,that the swing links succeeded the incline planes as a centering device was mainly because they were cheaper and simpler to construct1 and not1 as has been claimed1 that the ,v's wore out quickly4#ac ,illustration3 ,,figure #g4--;,bissell's #b-wheel truck of #aheh as shown by the drawing for ,british patent #bgea1 issued ,december #a1 #aheh4 ,smith's swing-bolster truck1 with the heart pendant link1 a later refinement1 became the dominating form of centering devices and was used well into this century4 ,it was to be superseded in more recent years by the constant resistance and gear roller centering devices which1 like ,bissell's invention1 depended on the double incline plane principle4 ,the ,british-born engineer ,william ,s4 ,hudson1 superintendent of the ,rogers ,works and an early proponent of the ,bissell truck1 in #ahfd obtained a patent#ad for improving ,bissell's safety truck4 ,hudson contended that since the ,bissell arrangement had a fixed pivot point it could traverse only one given radius accurately4 ,he proposed to replace the fixed pivot with a radius bar 7see fig4 #e7 one end of which was attached to the locomotive under the smoke-box and the other to rear of the truck frame1 at the same point of attachment as in the ,bissell plan4 ,thus1 according to ,hudson1 the pivot point could move laterally so that the truck might more easily accommodate itself to a curve of any radius4 ,he further claimed that a better distribution of weight was effected and that the use of the radius bar relieved the center bearing casting of much of the strain of propelling the truck4 ,illustration3 ,,figure #h4--;,a #b-wheel ,bissell truck installed on the ,pennsylvania ,railroad's ,no4 #ia4 ,this engine originally an #j-h-j ,winans ,camel built in ,february #ahed1 was rebuilt by ,john ,p4 ,laird in #ahfg1 at which time the ,bissell truck was added4 ,note that ,hudson equalizing lever was not used4 7,smithsonian photo #dfhjf-k7 ,the ,british journal ,engineering1 in an article otherwise friendly to the inventor1 expressed some skepticism as to the real merit of ,hudson's invention4#ae ,if ,mr4 ,hudson's truck1 444 be examined1 it will be seen that the radius link serves no other purpose than that of carrying the truck along with the engine1 and this could obviously be equally done by the pivot or central pin of the truck itself4 ,it is probable that few builders other than ,rogers made use of the ,hudson radial link4#af ,one of these was ,john ,headden1 whose ,general ,darcy1 shown in figure #f1 was fitted with the ,hudson truck4 ,thus1 by #ahfj there had been perfected and adopted a successful #d-wheel safety truck for #d-d-j's and #d-f-j's used in general mixed and passenger service4 ,but as the decade advanced1 the need grew for heavy freight engines that could be safely run at speed4 ,without a pilot truck1 the leading driving axle of the freight engine was generally overloaded4 ,while the application of a #d-wheel truck reduced this front-end overload and permitted faster running it materially reduced the traction of the drivers by bearing too great a portion of the total weight4 ,this loss of traction was of course highly undesirable and generally disqualified the use of #d-wheel trucks for freight engines4 ,what was needed was a truck which would guide the #j-f-j's and #j-h-j's around curves and yet leave the greater portion of the weight on the drivers4 ,the #b-wheel1 or pony1 truck met these requirements4#ag ,illustration3 ,,figure #i4--,running gear and truck designed by ,john ,l4 ,whetstone1 as shown in the drawing for ,u4,s4 patent #bghej1 issued ,april #aj1 #ahfj4 ,levi ,bissell produced the basic patent for such a truck in #aheg4 ,zerah ,colburn in ,september of that year had suggested to ,bissell that he develop a #b-wheel truck4 ,such a device1 he believed1 would be well received in ,britain4#ah ,he was quite correct1 as will shortly be seen4 ,in nearly every respect ,bissell's #b-wheel truck 7see fig4 #g7 followed the idea of the original patent for the #d-wheel truck1 which he claimed as the basis for the present invention4 ,the pintle was located behind the truck axle1 near the front driving-wheel axle1 and the weight was carried by incline planes that also served as the centering device4 ,a study of the patent drawing in figure #g reveals several interesting points4 ,note that the ,v's1 and thus the point of bearing1 are slightly in front of the center line of the truck axle4 ,it was suggested in the patent specification that the ,v's might be placed to the front1 rear1 or directly over the axle1 but in most actual applications they were placed directly over the axle4 ,note also that the locomotive shown on the figure is obviously a standard high-wheel ,american type which has suffered the rather awkward substitution of a pony truck for its regular #d-wheel arrangement4 ,it is probable that few if any ,american types were so rebuilt4 ,bissell was granted ,u4,s4 patent #baicf on ,november #b1 #aheh4 ,british patent #bgea was issued for the same device on ,december #a1 #aheh4 ,a few months later1 in the summer of #ahei1 service tests of ,bissell's new truck began in ,england4 ,first known use of the truck was on the ,british ,eastern ,counties ,railway ,no4 #bdh1 a rigid-frame #b-d-j built by ,kitson in #ahee4 ,the leading wheels of the engine1 as originally constructed1 were attached to the frame in the same manner as the drivers and thus had no lateral freedom4 ,for the test the front pedestals1 which held the journal boxes of the leading wheels1 were cut off and a ,bissell pony truck was substituted4 ,about a year later ,alexander ,l4 ,holley reported on the success of the test4#ai ,the #bdh had operated #ag1ejj miles1 at speeds up to #ej m4p4h41 safely and satisfactorily4 ,the engine not only rode more steadily but showed a remarkable reduction in flange wear4 ,the road was so pleased that by #ahff they had equipped #ba locomotives with ,bissell trucks4#bj ,several other ,british lines followed the example of the ,eastern ,counties ,railway4 ,illustration3 ,,figure #aj4--,the ,hudson-,bissell truck permitted the introduction of ,mogul and ,consolidation type freight locomotives4 ,this drawing shows a typical installation for a ,consolidation of the #ahhj's4 ,item ,a is the equalizing lever which connects the truck to the springs of the front driving wheels4 ,from figures #hia-c in ,j4 ,g4 ,a4 ,meyer1 ,modern ,locomotive ,construction1 ,new ,york1 ,john ,wiley1 #aijd1 p4 #edc4 ,at first ,bissell's #b-wheel truck received wider application in ,europe than in this country1 because most ,american roads1 despite the interest in developing heavier freight locomotives1 continued to depend upon the #d-d-j as a dual-purpose machine4 ,it was not until after #ahgj1 when ,mogul and ,consolidation types appeared in greater numbers1 that the #b-wheel truck became common in the ,united ,states4 ,the first use1 known to the writer1 of the ,bissell pony in this country occurred in ,november or ,december of #ahei on the ,memphis and ,charleston ,railroad4 ,d4 ,h4 ,feger1 master mechanic of the railroad reported1 eight months later1 that since the locomotive had been fitted with the ,bissell truck she has never left the rail and previous to her having this truck she was off the rail almost daily4#ba ,in the same report ,feger stated that he planned to re-equip another locomotive in the same manner4 ,illustration3 ,,anthracite ,,coal ,,burning ,,freight ,,locomotive ,,rogers ,,locomotive ,,machine ,,works ,,figure #aa4--,the ,new ,jersey ,railroad and ,transportation ,company ,no4 #cf1 built by the ,rogers ,locomotive and ,machine ,works in #ahfc1 was one of the first locomotives to be equipped by this firm with a #b-wheel ,bissell truck4 7,smithsonian photo #dfhjf-m7 ,the ,baldwin ,locomotive ,works in ,december #ahfj built a group of rather awkward looking #b-f-j's for the ,louisville and ,nashville ,railroad4 ,equipped with ,bissell trucks1 these were undoubtedly among the very first new locomotives to be so built4 ,the first consolidation type was built by ,baldwin in #ahff2 it was equipped with a #b-wheel ,bissell safety truck4 ,the ,rogers ,locomotive and ,machine ,works and the ,new ,jersey ,locomotive and ,machine ,works1 both of ,paterson1 ,new ,jersey1 in the early #ahfj's began building ,moguls2 these are known to have had ,bissell trucks4 ,other builders followed their example1 so that by the #ahgj's #b-wheel trucks had become relatively common4 ,it should be noted that the #b-wheel truck was not an absolute success until it was equalized with the front driving axle4 ,this arrangement was perfected in #ahfd by ,william ,s4 ,hudson1 but before describing his invention it will be helpful to discuss several earlier attempts to equalize pony trucks with the drivers4 ,in #aheg ,john ,p4 ,laird1 then master mechanic of the ,marietta and ,cincinnati ,railroad1 rebuilt an old ,niles #h-wheeler into a curious #b-f-j on which only the two rear driving wheels were coupled4 ,the front driver was driven by a chain and sprocket1 and the pilot wheels were equalized with the front driving axle4 ,the success or failure of the arrangement has not been definitely determined1 but whatever the outcome1 ,laird continued his experiments when he became superintendent of motive power for the ,pennsylvania ,railroad in #ahfb4 ,he abandoned the chain drive for a more conventional arrangement of side rods1 but the truck and his plan of equalization were much the same as that tried earlier4 ,laird used two equalizing levers1 attached at one end to the front spring hangers and at the other to the truck1 but in a way to allow the truck to swing horizontally4 ,the fulcrum for each lever was mounted on the underside of the front frame rail4 ,a number of old #h-wheel ,baldwin flexible-beam engines and several ,winans' ,camels were rebuilt in this way4 ,one of these is shown in figure #h4 ,laird1 however1 eventually became dissatisfied with his arrangement and re-equipped the engines with ,bissell trucks4 ,illustration3 ,,locomotive ,,engine ,,safety ,,truck ,,co4 ,,of ,,new ,,york4 ,proprietors of the following ,letters ,patent granted to ,levi ,bissell1 ,aug4 #d1 #aheg1 ,nov4 #b1 #aheh 7extended ,nov4 #b1 #ahgb72 ,a4 ,w4 ,smith1 ,feb4 #aa1 #ahfb2 ,d4 ,r4 ,pratt4 ,oct4 #af1 #ahfj2 ,w4 ,s4 ,hudson1 ,april #e1 #ah;digits missing and ,may #aj1 #ahfd4 ,,drawings ,,furnished ,,and ,,licenses ,,granted ,,on ,,application4 ,a4 ,f4 ,,smith1 ,president4 ,m4 ,f4 ,,moore1 ,sec'y and ,agent ,,albert ,,bridges4 ,treas4 ,no #df ,cortlandt st4 ,n4 ,y4 ,,figure #ab4--,notice of the ,locomotive ,safety ,truck ,company listing the patents held by it4 ,from ,railroad ,gazette1 ,march #c1 #ahgf4 ,john ,l4 ,whetstone on ,april #aj1 #ahfj1 obtained ,u4,s4 patent #bghej1 which strikingly anticipated the plan ,hudson was to develop four years later4#bb ,whetstone did not use a ,bissell truck and was in fact more concerned in relieving the excess weight1 often a #ej overload1 from the front axle of #j-f-j locomotives and in distributing a portion of that weight to a pony truck4 ,his arrangement may be readily understood from the patent drawing in figure #i4 ,probably the best features of the design was the transverse ,h-beam that connected the spring hangers to the truck frame1 which in this case also served as the equalizing lever 7note that the ball ,c acts as the fulcrum74 ,hudson made use of this same device but in a more practical manner4 ,he found that while the ,bissell pony truck could satisfactorily adjust itself laterally and could lead the locomotive around curves1 it could not handle the varying loads imposed upon it by the rough trackage typical of ,american railroads4 ,at one moment an undue amount of weight would fall upon the truck because the drivers were over a depression in the roadbed4 ,this condition overloaded the truck's springs and also resulted in a momentary loss of adhesion1 causing the drivers to slip4 ,conversely1 when the truck hit a depression too much weight was thrust upon the driving wheels1 and broken springs or other damage might result4 ,hudson's ingenious remedy to this problem was simple and straightforward 7see fig4 #aj74 ,a heavy equalizing lever that connected the truck to the springs of the front driving wheels was placed on the longitudinal centerline of the locomotive1 with the fulcrum under the cylinder saddle4 ,thus the truck and front driver reacted together to all the inequalities and shocks offered by the roadbed4 ,in ,october of #ahfc1 under ,hudson's direction1 two #b-f-j's equipped with ,bissell trucks were built at the ,rogers ,works for the ,new ,jersey ,railroad and ,transportation ,company4 ,probably some fault was found with the suspension of these machines1 numbered #ce and #cf1 for the next #b-f-j1 numbered #ci1 built for the ,new ,jersey road was equipped with ,hudson's equalizer4 ,this engine1 completed in ,january #ahfe1 is believed to be the first ,mogul so equipped4#bc ,the ,locomotive ,engine ,safety ,truck ,company 7see fig4 #aa7 was formed in the #ahgj's1 with ,a4 ,f4 ,smith as president1 to exploit the patents of ,bissell1 ,smith1 and ,hudson4 ,for several years notices appeared in the columns of the ,railroad ,gazette reporting suits by the ,company against various railroads and locomotive builders for unauthorized use of their patents4 ,the ,gazette of ,may #bi1 #ahge1 carries a protest of the ,company against the ,manchester ,locomotive ,works for unlicensed use of ,smith's patent of #ahfb4 ,in the issue of ,august #bh1 #ahge1 is reported the ,company's success in establishing the validity of ,smith's patent3 ,some important settlements for the use of the patent have lately been made with the company1 one of them being with the ,western ,railroad ,association1 whose headquarters are at ,chicago1 which includes the principal western roads4 ,through this the company receives its royalty on several hundred locomotives4 ,,in ,,summary ,it can be stated that ,hudson's modification of the ,bissell truck is of unquestioned importance1 for without the introduction of the equalizer it is doubtful if the #b-wheel pony truck would have been a complete success on ,american railroads4 ,bissell's #d-wheel truck was extensively employed1 but it did not enjoy the universal popularity of the #b-wheel truck1 and in the #ahhj's was eclipsed by other forms of #d-wheel safety trucks4 ,the ,hudson-,bissell pony truck1 however1 survived in its basic form to recent times1 when1 in the late #aidj's and early #aiej's1 the last steam locomotives were constructed in this country4 #a4 ,three-point suspension in a #d-b-j was easily gained--the center plate of the truck and the two bearings of the driving wheel axle4 ,on a #d-d-j the center plate served as one point1 while the fulcrum of each equalizing lever served as the other two points1 thus providing the desirable and highly stable #c-point suspension4 #b4 ,american ,railroad ,journal1 #ahec1 vol4 #i1 p4 #dbg4 #c4 ,connecting both truck axles with an equalizing lever so that they acted in sympathy with each other also did much to prevent derailments on rough trackage4 #d4 ,bissell states in the patent specification that inclined planes had been previously applied to railroad car trucks4 ,his claim rested on the application of this device to locomotive trucks4 #e4 ,from a sworn statement of ,g4 ,m4 ,milligan dated ,july #b1 #aheg4 ,this along with letters1 petitions1 receipts1 and other such material quoted in this discussion are from the ,patent ,office papers housed in the ,national ,archives1 ,washington1 ,d4,c4 7hereafter referred to as ,patent ,office papers74 #f4 ,the ,lebanon was a #d-d-j1 used in freight service1 that had been built by the ,new ,jersey ,locomotive and ,machine ,company in ,december #ahee4 #g4 ,letter dated ,july #b1 #aheg1 from ,s4 ,l4 ,moore 7,patent ,office papers74 #h4 ,statement cited in footnote #e4 #i4 ,letter dated ,july #aa1 #aheg1 ,charles ,mason to ,levi ,bissell 7,patent ,office papers74 #aj4 ,american ,railway ,review1 ,february #i1 #ahfj1 vol4 #b1 p4 #ga4 #aa4 ,u4,s4 patent #cdcgg1 ,february #aa1 #ahfb4 #ab4 ,davenport ,bridges1 car builders of ,cambridge1 ,massachusetts1 in #ahda1 obtained a ,u4,s4 patent for a swing-beam truck4 #ac4 ,gustavus ,weissenborn in his authoritative ,american ,locomotive ,engineering and ,railway ,mechanism 7,new ,york1 #ahga1 p4 #aca71 stated that when in use the ,v's soon acquired a polished surface which seemed to defy wear4 #ad4 ,u4,s4 patent #dbffb1 ,may #aj1 #ahfd4 #ae4 ,engineering1 ,july #ab1 #ahfg1 vol4 #d1 p4 #bi4 #af4 ,john ,headden1 master mechanic of the ,new ,jersey ,railroad and ,transportation ,company1 built at the road's ,jersey ,city shops several locomotives equipped with ,hudson's variety of the ,bissell truck4 ,headden1 upon the death of ,hudson1 succeeded him in #ahha as superintendent of the ,roger ,works4 #ag4 ,it is believed that ,harrison1 ,winans and ,eastwick made one of the first uses of a #b-wheel radial truck on a #b-f-j built at the ,alexandrovsky ,arsenal1 ,st4 ,petersburg1 in #ahdd-df4 ,the success or exact particulars of these machines is unknown4 ,see ,john ,jahn1 ,die ,dampflokomotive in ,entwicklungsgeschichtlicher ,darstellung ,ihres ,gesamtaufbaues1 ,berlin1 #aibd1 p4 #bci2 ,richard ,e4 ,peunoyer1 ,messrs4 ,harrison1 ,winans ,eastwick1 ,st4 ,petersburg1 ,russia1 ,railway and ,locomotive ,historical ,society ,bulletin no4 #dg1 ,september #aich1 p4 #df2 and ,joseph ,harrison1 ,jr41 ,the ,locomotive ,engine1 and ,philadelphia's ,share in its ,early ,improvements1 ,philadelphia1 #ahgb1 p4 #eb4 #ah4 ,zerah ,colburn1 ,locomotive ,engineering and the ,mechanism of ,railways1 4441 ,london1 #ahga1 p4 #ii4 ,zerah ,colburn 7#ahcb-ahgj7 was one of the best informed and most vocal authorities on #aith-century ,american locomotive construction4 ,he not only designed advanced machines while working at the ,new ,jersey ,locomotive ,works but also advocated many reforms in locomotive design4 ,he published the ,railroad ,advocate in ,new ,york ,city for several years4 ,in #aheh he became editor of ,the ,engineer and in #ahff founded the technical journal ,engineering4 #ai4 ,american ,railway ,review1 ,june #h1 #ahfj1 vol4 #b1 p4 #cib4 ,holley was a well known authority on locomotive engineering and the author of several books on the subject4 #bj4 ,engineering ,may #aa1 #ahff1 vol4 #a1 p4 #cac4 ,by this time 7#ahff71 the ,eastern ,counties ,railway had become part of the ,great ,eastern system4 #ba4 ,american ,railway ,review ,july #bf1 #ahfj1 vol4 #b1 p4 #ch4 #bb4 ,whetstone was chief designer for ,niles ,co41 a ,cincinnati locomotive builder4 ,his invention apparently did not receive a test1 since the company closed shortly before the patent was granted4 ,no other builder seemed interested4 #bc4 ,paul ,t4 ,warner1 ,mogul ,type ,locomotives1 ,railway and ,locomotive ,historical ,society ,bulletin no4 #ajj1 ,april #aiei4 ,u4,s4 ,,government ,,printing ,,office3 #aifa ,for sale by the ,superintendent of ,documents1 ,u4,s4 ,government ,printing ,office1 ,washington #be1 ,d4,c4--,price #bj cents